little help please (knocking noise)

[dereklschmidt]

I'm asking this for a friend of mine I ride with. He's got an 03' LTZ400 piped and jetted. Last few times we've been out he's thrown the chain, not a big deal, got a new chain and sprocket set coming.

We got it back on this last time, now every once in awhile it'll make a knocking noise. The noise is not conistan, meaning it's not all the time. When we do hear it, it does not seem to speed up with the throttle nor get louder. If it does change, it is hardly enough to notice. Which is weird to me and throwing me for a loop. However, it does do it at idle as well, kind of a constant "tick...tick...tick...tick...tick..."

But like I said, it doesn't do it all the time, it's almost at random. I couldn't get it to constantly do it after a certain rpm, shift, stop, or anything. And it could be just a coincidence that it happened at the same time as he threw the chain last, may not have anything to do with the chain coming off.

Any help would be greatly appreciated, just looking for some suggestions and ideas. THANKS IN ADVANCE.

[Villageidiott83]

my only guess, cam chain could be goin bad, or check the valves.

[YFZ450Ridr]

the cam chain is probablly worn out and somewhat 'flapping' around making the noise. pretty common for this to happen, especially on an 03 with lots of hours. check that out first!

[dereklschmidt]

thanks for the help guys, we'll look into it here shortly hopefully.

[Hotshoe18]

The race cars i drive are 600cc streetbike engine powered sprint cars and when you throw a chain on one of those, their real bad to float a valve or something. I also raced karts and when THEY threw a chain, they would always stretch a cam chain. More than likely its one of those but its definantly from throwing the chain

[dereklschmidt]

UPDATE!!!:

Ok, so I had him pull the cam tensioner this morning to see if the cam chain needs adjusted or not.

I attached the pic of the tensioner, I am assuming that this picture shows that the Cam Chain needs to be replaced by how many clicks are shown on the adjustment of the auto tensioner.

Am I right here? Also, giving the status of it, and this is what is making the noise, how much damage can come from running it like this for a few months? Maybe riding once a week or so, mostly trails, some dunes & some jumping. Would it be ok till winter to change it out or is this a case that needs to be fixed asap before it damages anything else?

Sorry for all the questions, I haven't dealt alot with the cam chain & auto tensioner units.

Thanks Again!

http://img234.imageshack.us/img234/7632/camtensionerqz3.th.jpg (http://img234.imageshack.us/my.php?image=camtensionerqz3.jpg)

[Villageidiott83]

theoritically it wont cause damage unless the cam chain breaks. if it breaks then the damage will be horrible. most likely the engine will be done.

[86250rbanshee]

I found it on here a while back when I had to work on a LTZ400 for a customer, I hadn't poped one open yet, if the tensioner clicks more than 3 times the chain is worn pretty badly. Toss a new chain in check valves and be all set

[YFZ450Ridr]

Originally posted by Villageidiott83
theoritically it wont cause damage unless the cam chain breaks. if it breaks then the damage will be horrible. most likely the engine will be done.

not hardly, my buddy snapped one in his 450r and it just bent the intake valves.

[jonridesz400]

my o3 z400 does that same thing i just have it sitting until the shop will catch up to work on it but it usually happens when i turn and give it throttle even just a slight touch... i just got it not to long ago so im pretty uncomfortable working on it cus i have no clue wth im doing...

[z295]

Well, I'm actually the friend who owns the quad, and unfortunately it's nothing as simple as any of that. I finally determined that the noise did have some relation to the clutch, at was changing ever so slights. I pulled the right side of the case off, and found that the clutch was fine, the push rod, which I was hoping was bent, was fine. So, now, I jacked up the rear end, and spun the tires, and found the noise to be constant through all 5 gears. You can feel that when it hits the "ticking" spot, that it's in a bind. It's going to be something busted in the tranny, so thanks for all the help, but now I get to go elbow deep. Probably ought to still replace the cam chain while I'm in there though. Thanks again.

Joel

[drzoo2]

There is a thread I read about flywheel bolts.......let me find it.

z

[drzoo2]

Just a thought

http://atvstore.com/articles/stator_fix/

z